1. Field of the Invention
This invention relates to a vaccination chamber for chickens. More particularly, the invention is directed to a chamber for use in immunizing chickens or the like fowls by treating them with a vaccine which is sprayed in the chamber. In other words, with the device according to the invention, it is possible to vaccinate chickens or the like fowls through their respiratory tracts.
2. Description of the Prior Art
It is well known that a standard procedure for vaccinating chickens, immediately or soon after their birth, is to give them, individually and manually, an injection of a particular vaccine. The vapor immunization of fowls has been taught in U.S. Pat. No. 2,984,240, issued on May 16, 1961 to A. L. Eames. This Patent generally describes an apparatus wherein the vaccine vapors are gradually supplied and distributed throughout a vaccination chamber which is filled with chicken containers. Basically, by means of a fan, the aim is to achieve a continuous circulation of the vaccine vapors in the entire chamber. The invention taught by Eames is in great need of improvement, since it is not at all certain that all the chickens which are present in the vaccination chamber will in effect be vaccinated. Furthermore, the cabinet designed by Eames has no provision for preventing the vaccine vapors from leaking outside the apparatus during the vaccination period; and what is more serious, there is a problem of pollution of the environment once the vaccination is terminated and the chickens have to be removed from the vaccination chamber. Eames does not teach how it is possible to flush the atmosphere inside the chamber without letting the viral vapors contaminate the air surrounding the immunization chamber. There is therefore a need for an apparatus which is thoroughly effective in the vaccination of chickens or the like birds and which, at the same time is not polluting the atmosphere in the immediate vicinity of the vaccination chamber.
Various enclosures have been described in the prior art, mostly intended to be used as poultry egg hatchers. A non exhaustive list of prior Patents which teach various methods of circulation of the atmosphere within the enclosures includes the following:
______________________________________ U.S. Pat. No. 1,823,584 Sept. 15, 1931 A. W. Bruce U.S. Pat. No. 1,837,065 Dec. 15, 1931 E. M. Pierce U.S. Pat. No. 3,389,688 June 25, 1968 C. R. Springer U.S. Pat. No. 3,396,703 Aug. 13, 1968 H. B. Trussell U.S. Pat. No. 3,927,642 Dec. 23, 1975 Gerd Levin U.S. Pat. No. 4,274,364 June 23, 1981 D. A. Forseth ______________________________________
Springer teaches an air deflector with a convex surface, to be used in a hatcher for circulating air. Levin shows a fan and a heating means to be used in the same types of hatchers. Trussell discloses that air is drawn upwardly through two banks of trays of eggs, and then moves laterally and outside air can be introduced through baffles. In the incubation method of Forseth, the fluid is discharged into the path of air moving upwardly, and then the air moves laterally through two banks of trays containing hatching eggs. None of the references show that it is possible to circulate air loaded with particles of foreign matter while making sure that they are equally concentrated at any place inside the enclosure. Furthermore, none of the prior art references indicate that it is possible to prevent leaks toward the outside air.
References which are considered not pertinent are the following:
______________________________________ U.S. Pat. No. 2,702,503 Feb. 22, 1955 J. F. Wildhaber U.S. Pat. No. 2,734,444 Feb. 14, 1956 A. G. Lunn, Jr., et al U.S. Pat. No. 3,630,174 Dec. 28, 1971 R. S. Runkle U.S. Pat. No. 4,023,529 May 17, 1977 Jerome J. Landy ______________________________________